When the Reformers proclaimed the hope found in the gospel, they were teaching against many of the fundamental Catholic beliefs. In the case of eternal security (Perseverance of the Saints), they were teaching against the Catholic teaching of justification. For centuries, the traditional teaching of the Catholic Church regarding justification had largely been influenced by Romans 5:5. From that verse, many in the Church were led to believe that justification was the Holy Spirit pouring love into our hearts to make us more lovely. As they became more lovely, they became more justified in the sight of God. The question continually hovered over them, "Am I justified enough?" That led them to concoct the teaching of purgatory, a place where the sin that remained was purged. Christians were not hopeful people under such teaching because there was no true assurance to be found for the believer.
However, Romans 5:5 does not teach us what justification is, but rather teaches us spiritual growth. Paul's teaching of justification is found in the preceding chapter, and he concludes it in Romans 5:1, "Therefore, since we have been justified by faith, we have peace with God through our Lord Jesus Christ." It is by faith we are justified, not by our works or becoming more lovely.
The outcome of such preaching was assurance and hope. It was as if light was shining into the darkness that had pervaded the Church for some time. Indeed, some have said that the slogan which best encapsulates the work of the Reformation is the 16th Century Genevan motto, post tenebras lux (after darkness, light). It is no surprise that this teaching resulted in assurance and hope. Paul goes on to say in Romans 5:2 that "we rejoice in the hope of the glory of God." In other words, "We have great joy for we are sure we will experience the glory of God." From there, he argues that our suffering and our sin cannot remove us from Christ. Chapter 6 and 7 display the power of God over sin and the law in the believer. Chapter 8 closes with the most assuring passage that nothing can separate us from the love of God.
The Arminians did not take the same route as the Catholics concerning assurance since they were of a Reformed heritage. However, they still erred; meaning they did not provide the same assurance as for the Calvinist. In their fifth article of Remonstrance, they make it clear that to remain in the faith depended primarily on us. For those who believe, "Jesus Christ assists them through his Spirit in all temptations, extends to them his hand, and if only they are ready for the conflict, and desire his help, and are not inactive, keeps them from falling." Because of the clause, "if only," the reason Christ keeps Christians from falling is because they desired it. Perseverance in the faith is up to us according to this article. If we do our part, Christ will do His. That is the same as saying Christ will not do His part unless we do our part. In essence, according to this fifth article, we will not be saved unless we work for it.
Paul had some harsh words for anyone who took such a position. The Galatians are our Biblical example of those who add on some sort of work in order to be saved. "O foolish Galatians! Who has bewitched you?" (Galatians 3:1). This is a serious matter for Paul. He continues, "Are you so foolish? Having begun by the Spirit, are you now being perfected by the flesh?" How, in other words, can you perfect a spiritual work by doing a physical work? It is impossible! The same must be said for those who believe that we remain in the faith by our works. It is foolish to think that the faith and grace gifted to us by God (Eph. 2:8) need something from us to perfect them. There is no work we can do that would act as a key to unlocking the full potential of faith and grace.
There is biblical uncertainty when it comes to the Arminian notion of perseverance. If we are honest, we are not confident in our abilities. You know your heart much better than I do, but the opposite is also true. I know my shortcomings enough to know that I could not depend on myself for salvation. The other uncertainty which comes from the Arminians is the lack of Scripture which teaches their position. They even state it in their article,
"But whether they are capable, through negligence, of forsaking again the first beginning of their life in Christ, of again returning to this present evil world, of turning away from the holy doctrine which was delivered them, of losing a good conscience, of neglecting grace, that must be more particularly determined out of the Holy Scripture, before we ourselves can teach it with the full confidence of our mind."
When the Calvinists put together their section on the perseverance of the saints, they were most concerned with giving an answer to the daily indwelling sin which besets every Christian. It is a valid question: How can a Christian get into heaven if they daily fall short of the glory of God in one way or another? In their answer, a beautiful line stands out: "The weakness of the flesh cannot prevail against the power of God, who confirms and preserves true believers in a state of grace." Christians cannot lose their salvation because God will not let them.
These Calvinists were not, as their opponents thought, tying the loose ends they had created with their understanding of grace, election, and predestination, they were only reiterating what Paul, Peter, and the rest of Scripture taught. Paul, writing to the Ephesians, says "[Those who believed] were sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it." Peter, likewise in his epistle, writes,
"Blessed be the God and Father of our Lord Jesus Christ! According to his great mercy, he has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead, to an inheritance that is imperishable, undefiled, and unfading, kept in heaven for you, who by God's power are being guarded through faith for a salvation ready to be revealed in the last time."
Scripture is clear; God undeniably preserves His people. The book of Hebrews speaks of Jesus being the "author and finisher" of our faith (Hebrews 12:2 KJV). God is the one who is at work in us, and it is not because of our works that such is the case.
The main objection to this doctrine today is an existential objection. Many say, on the basis of their experience, that they know of many who have fallen from faith and a state of grace. However convincing their story, you will not find anything of the kind in Scripture. Jesus' parable of the soils portrays some as having rocky soil where the plant springs up with much energy and passion only to die and wither away because of a lack of nutrients and soil for the roots to grow. Another soil is full of weeds which choke out the seed. There are those who display the characteristics of faith in their lives only to come to the point where it is shown that there is no true faith residing in them (1 John 2:19).
The doctrine of the Perseverance of the Saints is the necessary close to these five points. If salvation is of God, then it must be of Him from start to finish. If salvation depends on our actions, it must depend on our actions from start to finish. What hope is there in depending on us for salvation? Do we have such a high view of ourselves that we fail to see our inadequacies to save ourselves? Scripture gives us hope when it declares that God alone is the one who saves. "I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ" (Phil. 1:6).